Zooming optical system, optical apparatus and method for manufacturing zooming optical system

ABSTRACT

A compact zooming optical system, an optical apparatus and a method for manufacturing the zooming optical system having a vibration reduction function, a high zooming ratio, a wide-angle view and superb optical performance are provided, the system including, in order from an object side: a first lens group G 1  having positive refractive power; a second lens group G 2  having negative refractive power; a third lens group G 3  having positive refractive power; and a fourth lens group G 4  having negative refractive power; upon zooming from a wide-angle end state to a telephoto end state, a distance between the first lens group G 1  and the second lens group G 2 , a distance between the second lens group G 2  and the third lens group G 3  and a distance between the third lens group G 3  and the fourth lens group G 4  being respectively varied; the third lens group G 3  having, in order from the object side, a first segment group G 31  having positive refractive power and a second segment group G 32 ; the second segment group G 32  being moved to have a component in a direction perpendicular to the optical axis; and predetermined conditional expressions being satisfied.

TECHNICAL FIELD

The present invention relates to a zooming optical system, an opticalapparatus and a method for manufacturing the zooming optical system.

BACKGROUND ART

There has hitherto been proposed a zooming optical system suitable for aphototaking camera, an electronic still camera, a video camera and thelike. For example, refer to Japanese Patent Application Laid-OpenPublication No. 2006-284763.

PRIOR ART DOCUMENT Patent Document

Patent Document 1:

-   Japanese Patent Application Laid-Open Publication No. 2006-284763

SUMMARY OF THE INVENTION Problem to be Solved by the Invention

However, there has been a problem that a conventional zooming opticalsystem is large in size and if high zooming ratio is intended whilevibration reduction function being maintained, its optical performanceis deteriorated remarkably.

Under such circumstances, the present invention is made in view of theabove-described problem, and has an object to provide a compact zoomingoptical system having a vibration reduction function, a high zoomingratio, a wide-angle view and superb optical performance, an opticalapparatus and a method for manufacturing the zooming optical system.

Means for Solving the Problem

According to a first aspect, there is provided a zooming optical systemincluding, in order from an object side: a first lens group havingpositive refractive power; a second lens group having negativerefractive power; a third lens group having positive refractive power;and a fourth lens group having negative refractive power;

upon zooming from a wide-angle end state to a telephoto end state, adistance between the first lens group and the second lens group, adistance between the second lens group and the third lens group and adistance between the third lens group and the fourth lens group beingrespectively varied;

the third lens group having, in order from the object side, a firstsegment group having positive refractive power and a second segmentgroup;

the second segment group being moved to have a component in a directionperpendicular to the optical axis; and the following conditionalexpression being satisfied:8.00<f1/(−f2)<10.00where f1 denotes a focal length of the first lens group, and f2 denotesa focal length of the second lens group.

According to a second aspect of the present invention, there is providedan optical apparatus having the zooming optical system according to thefirst aspect of the present invention.

According to a third aspect of the present invention, there is provideda zooming optical system including, in order from an object side: afirst lens group having positive refractive power; a second lens grouphaving negative refractive power; a third lens group having positiverefractive power; and a fourth lens group having positive refractivepower;

upon zooming from a wide-angle end state to a telephoto end state, adistance between the first lens group and the second lens group, adistance between the second lens group and the third lens group and adistance between the third lens group and the fourth lens group beingrespectively varied;

the third lens group having, in order from the object side, a firstsegment group having positive refractive power and a second segmentgroup;

the second segment group being moved to have a component in a directionperpendicular to the optical axis; and

the following conditional expression being satisfied:2.80<f1/f3<4.50where f1 denotes a focal length of the first lens group, and f3 denotesa focal length of the third lens group.

According to a fourth aspect of the present invention, there is providedan optical apparatus having the zooming optical system according to thethird aspect of the present invention.

According to a fifth aspect of the present invention, there is provideda zooming optical system including, in order from an object side: afirst lens group having positive refractive power; a second lens grouphaving negative refractive power; a third lens group having positiverefractive power; and a fourth lens group having positive refractivepower;

upon zooming from a wide-angle end state to a telephoto end state, adistance between the first lens group and the second lens group, adistance between the second lens group and the third lens group and adistance between the third lens group and the fourth lens group beingrespectively varied;

the third lens group having, in order from the object side, a firstsegment group having positive refractive power and a second segmentgroup;

the second segment group being moved to have a component in a directionperpendicular to the optical axis; and the following conditionalexpressions being satisfied:0.20<|f32|/f1<0.430.60<f31/f3<0.90where f1 denotes a focal length of the first lens group, f3 denotes afocal length of the third lens group, f31 denotes a focal length of thefirst segment group, and f32 denotes a focal length of the secondsegment group.

According to a sixth aspect of the present invention, there is providedan optical apparatus having the zooming optical system according to thefifth aspect of the present invention.

According to a seventh aspect, there is provided a method formanufacturing a zooming optical system comprising, in order from anobject side: a first lens group having positive refractive power; asecond lens group having negative refractive power; a third lens grouphaving positive refractive power; and a fourth lens group havingpositive refractive power;

said method comprising steps of

constructing the third lens group to include, in order from the objectside, a first segment group having positive refractive power and asecond segment group,

constructing the first lens group and the second lens group such thatthe following conditional expression may be satisfied:8.00<f1/(−f2)<10.00where f1 denotes a focal length of the first lens group, and f2represents a focal length of the second lens group, constructing suchthat a distance between the first lens group and the second lens group,a distance between the second lens group and the third lens group and adistance between the third lens group and the fourth lens group may bevaried respectively upon zooming to the telephoto end state from thewide-angle end state, and

constructing the second segment group to move in a direction having acomponent perpendicular to the optical axis.

According to an eighth aspect, there is provided a method formanufacturing a zooming optical system comprising, in order from anobject side: a first lens group having positive refractive power; asecond lens group having negative refractive power; a third lens grouphaving positive refractive power; and a fourth lens group havingpositive refractive power;

said method comprising steps of

constructing the third lens group to include, in order from the objectside, a first segment group having positive refractive power and asecond segment group,

constructing the first lens group and the third lens group such that thefollowing conditional expression may be satisfied:2.80<f1/f3<4.50where f1 denotes a focal length of the first lens group, and f3represents a focal length of the third lens group,

constructing such that a distance between the first lens group and thesecond lens group, a distance between the second lens group and thethird lens group and a distance between the third lens group and thefourth lens group respectively varied, upon zooming to the telephoto endstate from the wide-angle end state, and

constructing the second segment group to move in a direction having acomponent perpendicular to the optical axis.

According to a ninth aspect, there is provided a method formanufacturing a zooming optical system comprising, in order from anobject side: a first lens group having positive refractive power; asecond lens group having negative refractive power; a third lens grouphaving positive refractive power; and a fourth lens group havingpositive refractive power;

said method comprising steps of

constructing the third lens group to include, in order from an objectside, a first segment group having positive refractive power and asecond segment group,

constructing the first lens group and the third lens group such that thefollowing conditional expressions may be satisfied:0.20<|f32|/f1<0.430.60<f31/f3<0.90where f1 denotes a focal length of the first lens group, f3 represents afocal length of the third lens group, f31 denotes a focal length of thefirst segment group, and f32 represents a focal length of the secondsegment group,

constructing such that a distance between the first lens group and thesecond lens group, a distance between the second lens group and thethird lens group and a distance between the third lens group and thefourth lens group respectively varied upon zooming to the telephoto endstate from the wide-angle end state, and

constructing the second segment group to move in a direction having acomponent perpendicular to the optical axis.

Effect of the Invention

According to the present invention, there can be provided the compactzooming optical system that has the vibration reduction function, thehigh zooming ratio, the wide-angle view and the superb opticalperformance, the optical apparatus, and the method for manufacturing thezooming optical system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A, 1B and 1C are, respectively, sectional views in a wide-angleend state, an intermediate focal length state and a telephoto end state,of a zooming optical system according to a first Example relating to thefirst to third embodiments of the present application.

FIGS. 2A, 2B and 2C are, respectively, graphs showing variousaberrations in the wide-angle end state, the intermediate focal lengthstate and the telephoto end state, of the zooming optical systemaccording to the first Example of the present application upon focusingon infinity.

FIGS. 3A and 3B are, respectively, graphs showing meridional transverseaberrations in the wide-angle end state and the telephoto end state ofthe zooming optical system according to the first Example of the presentapplication, upon focusing on infinity and vibration reduction beingconducted.

FIGS. 4A, 4B and 4C are, respectively, the sectional views in thewide-angle end state, the intermediate focal length state and thetelephoto end state, of the zooming optical system according to a secondExample relating to the first to third embodiments of the presentapplication.

FIGS. 5A, 5B and 5C are, respectively, the graphs showing the variousaberrations in the wide-angle end state, the intermediate focal lengthstate and the telephoto end state, of the zooming optical systemaccording to the second Example of the present application upon focusingon the infinity.

FIGS. 6A and 6B are, respectively, graphs showing meridional transverseaberrations in the wide-angle end state and the telephoto end state ofthe zooming optical system according to the second Example of thepresent application, upon focusing on infinity and vibration reductionbeing conducted.

FIGS. 7A, 7B and 7C are, respectively, the sectional views in thewide-angle end state, the intermediate focal length state and thetelephoto end state, of the zooming optical system according to a thirdExample relating to the first to third embodiments of the presentapplication.

FIGS. 8A, 8B and 8C are, respectively, the graphs showing the variousaberrations in the wide-angle end state, the intermediate focal lengthstate and the telephoto end state, of the zooming optical systemaccording to the third Example of the present application upon focusingon the infinity.

FIGS. 9A and 9B are, respectively, graphs showing meridional transverseaberrations in the wide-angle end state and the telephoto end state ofthe zooming optical system according to the third Example of the presentapplication, upon focusing on infinity and vibration reduction beingconducted.

FIGS. 10A, 10B and 10C are, respectively, the sectional views in thewide-angle end state, the intermediate focal length state and thetelephoto end state, of the zooming optical system according to a fourthExample relating to the first to third embodiments of the presentapplication.

FIGS. 11A, 11B and 11C are, respectively, the graphs showing the variousaberrations in the wide-angle end state, the intermediate focal lengthstate and the telephoto end state, of the zooming optical systemaccording to the fourth Example of the present application upon focusingon the infinity.

FIGS. 12A and 12B are, respectively, graphs showing meridionaltransverse aberrations in the wide-angle end state and the telephoto endstate of the zooming optical system according to the fourth Example ofthe present application, upon focusing on infinity and vibrationreduction being conducted.

FIGS. 13A, 13B and 13C are, respectively, the sectional views in thewide-angle end state, the intermediate focal length state and thetelephoto end state, of the zooming optical system according to a fifthExample relating to the first to third embodiments of the presentapplication.

FIGS. 14A, 14B and 14C are, respectively, the graphs showing the variousaberrations in the wide-angle end state, the intermediate focal lengthstate and the telephoto end state, of the zooming optical systemaccording to the fifth Example of the present application upon focusingon the infinity.

FIGS. 15A and 15B are, respectively, graphs showing meridionaltransverse aberrations in the wide-angle end state and the telephoto endstate of the zooming optical system according to the fifth Example ofthe present application, upon focusing on infinity and vibrationreduction being conducted.

FIGS. 16A, 16B and 16C are, respectively, the sectional views in thewide-angle end state, the intermediate focal length state and thetelephoto end state, of the zooming optical system according to a sixthExample relating to the first to third embodiments of the presentapplication.

FIGS. 17A, 17B and 17C are, respectively, the graphs showing the variousaberrations in the wide-angle end state, the intermediate focal lengthstate and the telephoto end state, of the zooming optical systemaccording to the sixth Example of the present application upon focusingon the infinity.

FIGS. 18A and 18B are, respectively, graphs showing meridionaltransverse aberrations in the wide-angle end state and the telephoto endstate of the zooming optical system according to the sixth Example ofthe present application, upon focusing on infinity and vibrationreduction being conducted.

FIG. 19 is a view showing a configuration of a camera equipped withzooming optical system according to the first to third embodiments ofthe present application.

FIG. 20 is a flowchart schematically showing a method for manufacturingthe zooming optical system relating the first embodiment of the presentapplication.

FIG. 21 is a flowchart schematically showing a method for manufacturingthe zooming optical system relating the second embodiment of the presentapplication.

FIG. 22 is a flowchart schematically showing a method for manufacturingthe zooming optical system relating the third embodiment of the presentapplication.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

A zooming optical system, an optical apparatus and a method formanufacturing the zooming optical system according to a first embodimentof the present application will hereinafter be described.

The zooming optical system according to the first embodiment of thepresent application includes, in order from an object side: a first lensgroup having positive refractive power; a second lens group havingnegative refractive power; a third lens group having positive refractivepower; and a fourth lens group having negative refractive power; uponzooming from a wide-angle end state to a telephoto end state, a distancebetween the first lens group and the second lens group, a distancebetween the second lens group and the third lens group and a distancebetween the third lens group and the fourth lens group are respectivelyvaried; the third lens group has, in order from the object side, a firstsegment group having positive refractive power and a second segmentgroup; the second segment group is moved to have a component in adirection perpendicular to the optical axis; and the followingconditional expression (1) is satisfied:8.00<f1/(−f2)<10.00  (1)where f1 denotes a focal length of the first lens group, and f2 denotesa focal length of the second lens group.

The zooming optical system according to the first embodiment of thepresent application, as described above, with the second segment groupin the third lens group being moved to include a component in adirection perpendicular to the optical axis, is thereby enabled tocorrect an image blur caused by a camera shake, i.e., to reducevibrations.

The conditional expression (1) described above defines a focal length ofthe first lens group with respect to the focal length of the second lensgroup. The zooming optical system according to the first embodiment ofthe present application satisfies the conditional expression (1) and isthereby enabled to preferably correct a curvature of field in thewide-angle end state, and to preferably correct a spherical aberrationin the telephoto end state.

When a corresponding value of the conditional expression (1) of thezooming optical system according to the first embodiment of the presentapplication exceeds an upper limit value, a zooming effect of the firstlens group decreases. Therefore, the refractive power of the second lensgroup needs to increase for ensuring a zooming ratio, resultingundesirably in causing occurrence of the curvature of field in thewide-angle end state and occurrence of the spherical aberration in thetelephoto end state. Note that the upper limit value of the conditionalexpression (1) is set to, more preferably, 9.70 for further ensuring theeffects of the present application.

Whereas when the corresponding value of the conditional expression (1)of the zooming optical system according to the first embodiment of thepresent application decreases below a lower limit value, the refractivepower of the first lens group increases, and it is undesirably difficultto correct the spherical aberration in the telephoto end state. It is tobe noted that the lower limit value of the conditional expression (1) isset to, more preferably, 8.10 for further ensuring the effects of thepresent application.

With this configuration described above, it is feasible to realize thecompact zooming optical system having a vibration reduction function, ahigh zooming ratio, a wide-angle view and superb optical performance.

It is desirable that the second segment group of the zooming opticalsystem according to the first embodiment of the present application hasnegative refractive power. With this configuration, the zooming opticalsystem according to the first embodiment of the present application isscaled down, and it is possible to restrain variation in the coma whenbeing eccentric.

Further, it is desirable that the zooming optical system according tothe first embodiment of the present application satisfies the followingconditional expression (2).0.60<f3/f4<0.90  (2)where f3 denotes a focal length of the third lens group, and f4 denotesa focal length of the fourth lens group.

The conditional expression (2) defines the focal length of the thirdlens group with respect to the focal length of the fourth lens group.The zooming optical system according to the first embodiment of thepresent application satisfies the conditional expression (2) and isthereby enabled to preferably correct the curvature of field and thecoma in the wide-angle end state, and to preferably correct thespherical aberration in the telephoto end state.

When the corresponding value of the conditional expression (2) of thezooming optical system according to the first embodiment of the presentapplication exceeds the upper limit value, the refractive power of thefourth lens group rises, and it is undesirably difficult to correct thecurvature of field and the coma in the wide-angle end state. Note thatthe upper limit value of the conditional expression (2) is set to, morepreferably, 0.85 for further ensuring the effects of the presentapplication.

Whereas when the corresponding value of the conditional expression (2)of the zooming optical system according to the first embodiment of thepresent application decreases below the lower limit value, therefractive power of the third lens group increases, and it isundesirably difficult to correct the spherical aberration particularlyin the telephoto end state. It is to be noted that the lower limit valueof the conditional expression (2) is set to, more preferably, 0.65 forfurther ensuring the effects of the present application.

Furthermore, it is desirable that the zooming optical system accordingto the first embodiment of the present application satisfies thefollowing conditional expression (3).2.80<f1/f3<4.50  (3)where f1 denotes the focal length of the first lens group, and f3denotes the focal length of the third lens group.

The conditional expression (3) defines the focal length of the firstlens group with respect to the focal length of the third lens group. Thezooming optical system according to the first embodiment of the presentapplication satisfies the conditional expression (3) and is therebyenabled to preferably correct the curvature of field in the wide-angleend state, and to preferably correct the spherical aberration in thetelephoto end state.

When the corresponding value of the conditional expression (3) of thezooming optical system according to the first embodiment of the presentapplication exceeds the upper limit value, the zooming effect of thefirst lens group decreases. Hence, the refractive power of the secondlens group needs to increase for ensuring the zooming ratio, resultingundesirably in causing the occurrence of the curvature of field in thewide-angle end state and the occurrence of the spherical aberration inthe telephoto end state. Note that the upper limit value of theconditional expression (3) is set to, more preferably, 4.30 for furtherensuring the effects of the present application.

Whereas when the corresponding value of the conditional expression (3)of the zooming optical system according to the first embodiment of thepresent application decreases below the lower limit value, therefractive power of the first lens group increases, and it isundesirably difficult to correct the spherical aberration in thetelephoto end state. It is to be noted that the lower limit value of theconditional expression (3) is set to, more preferably, 3.00 for furtherensuring the effects of the present application.

Moreover, it is desirable for the zooming optical system according tothe first embodiment of the present application satisfies the followingconditional expression (4).2.20<f1/f4<3.50  (4)where f1 denotes the focal length of the first lens group, and f4denotes the focal length of the fourth lens group.

The conditional expression (4) defines the focal length of the firstlens group with respect to the focal length of the fourth lens group.The zooming optical system according to the first embodiment of thepresent application satisfies the conditional expression (4) and isthereby enabled to preferably correct the curvature of field and thecoma in the wide-angle end state, and to preferably correct thespherical aberration in the telephoto end state.

When the corresponding value of the conditional expression (4) of thezooming optical system according to the first embodiment of the presentapplication exceeds the upper limit value, the refractive power of thefourth lens group rises, and it is undesirably difficult to correct thecurvature of field and the coma in the wide-angle end state. Note thatthe upper limit value of the conditional expression (4) is set to, morepreferably, 3.30 for further ensuring the effects of the presentapplication.

Whereas when the corresponding value of the conditional expression (4)of the zooming optical system according to the first embodiment of thepresent application decreases below the lower limit value, therefractive power of the first lens group increases, and it isundesirably difficult to correct the spherical aberration particularlyin the telephoto end state. It is to be noted that the lower limit valueof the conditional expression (4) is set to, more preferably, 2.50 forfurther ensuring the effects of the present application.

Further, in the zooming optical system according to the first embodimentof the present application, it is desirable that at least a part of thesecond lens group moves along the optical-axis when focusing. Thefocusing is conducted by at least a part of the compact and light-weightsecond lens group, whereby quick focusing can be attained.

Moreover, it is desirable that the zooming optical system according tothe first embodiment of the present application satisfies the followingconditional expression (5).0.20<|f32|/f1<0.43  (5)where f1 denotes the focal length of the first lens group, and f32denotes the focal length of the second segment group.

The conditional expression (5) defines the focal length of the secondsegment group with respect to the focal length of the first lens group.The zooming optical system according to the first embodiment of thepresent application satisfies the conditional expression (5) and isthereby enabled to preferably correct the spherical aberration in thetelephoto end state, and to preferably correct the coma when moving thesecond segment group to include the component in a directionperpendicular to the optical axis.

When the corresponding value of the conditional expression (5) of thezooming optical system according to the first embodiment of the presentapplication exceeds the upper limit value, the refractive power of thefirst lens group rises, and it is undesirably difficult to correct thespherical aberration in the telephoto end state. Note that the upperlimit value of the conditional expression (5) is set to, morepreferably, 0.41 for further ensuring the effects of the presentapplication.

Whereas when the corresponding value of the conditional expression (5)of the zooming optical system according to the first embodiment of thepresent application decreases below the lower limit value, therefractive power of the second segment lens group increase. It istherefore undesirable to cause deterioration of the coma when moving thesecond segment lens group to include the component in a directionperpendicular to the optical axis. It is to be noted that the lowerlimit value of the conditional expression (5) is set to, morepreferably, 0.25 for further ensuring the effects of the presentapplication.

Further, it is desirable that the second segment group of the zoomingoptical system according to the first embodiment of the presentapplication is configured to include a cemented lens having one positivelens and one negative lens. With this configuration, the decenteringcoma can be preferably corrected when moving the second segment group toinclude the component in a direction perpendicular to the optical axis.

Furthermore, it is desirable that the zooming optical system accordingto the first embodiment of the present application satisfies thefollowing conditional expression (6).0.35<(−f2)/f3<0.55  (6)where f2 denotes the focal length of the second lens group, and f3denotes the focal length of the third lens group.

The conditional expression (6) defines the focal length of the secondlens group with respect to the focal length of the third lens group. Thezooming optical system according to the first embodiment of the presentapplication satisfies the conditional expression (6) and is therebyenabled to preferably correct the curvature of field in the wide-angleend state, and to preferably correct the spherical aberration in thetelephoto end state.

When the corresponding value of the conditional expression (6) of thezooming optical system according to the first embodiment of the presentapplication exceeds the upper limit value, the zooming effect of thefirst lens group decreases. Hence, the refractive power of the firstlens group needs to increase for ensuring the zooming ratio, resultingundesirably in causing the occurrence of the curvature of field in thewide-angle end state and the occurrence of the spherical aberration inthe telephoto end state. Note that the upper limit value of theconditional expression (6) is set to, more preferably, 0.52 for furtherensuring the effects of the present application.

Whereas when the corresponding value of the conditional expression (6)of the zooming optical system according to the first embodiment of thepresent application decreases below the lower limit value, the zoomingeffect of the third lens group decreases. Therefore, the refractivepower of the first lens group or the second lens group needs to increasefor ensuring the zooming ratio, resulting undesirably in the difficultyto correct the spherical aberration in the telephoto end state and tocorrect the curvature of field in the wide-angle end state. Note thatthe lower limit value of the conditional expression (6) is set to, morepreferably, 0.38 for further ensuring the effects of the presentapplication.

Moreover, it is desirable that the first lens group of the zoomingoptical system according to the first embodiment of the presentapplication moves along the optical-axis when zooming to the telephotoend state from the wide-angle end state. With this configuration, therefractive power of each of the respective lens groups relating to thezooming, i.e., of the first to fourth lens groups can be decreased, andit is feasible to ensure the preferable optical performance covering thewide-angle end state and the telephoto end state throughout.

The optical apparatus of the present application is characterized byhaving the zooming optical system configured as described aboveaccording to the first embodiment. This configuration enablesactualization of the compact optical apparatus having the vibrationreduction function, the high zooming ratio, the wide-angle view and thesuperb optical performance.

A method for manufacturing the zooming optical system according to thefirst embodiment of the present application is a method formanufacturing the zooming optical system comprising, in order from anobject side: a first lens group having positive refractive power; asecond lens group having negative refractive power; a third lens grouphaving positive refractive power; and a fourth lens group havingpositive refractive power;

said method comprising steps of

constructing the third lens group to include, in order from the objectside, a first segment group having positive refractive power and asecond segment group,

constructing the first lens group and the second lens group such thatthe following conditional expression (1) may be satisfied:8.00<f1/(−f2)<10.00  (1)where f1 denotes a focal length of the first lens group, and f2represents a focal length of the second lens group,

constructing such that a distance between the first lens group and thesecond lens group, a distance between the second lens group and thethird lens group and a distance between the third lens group and thefourth lens group may be varied respectively upon zooming to thetelephoto end state from the wide-angle end state, and

constructing the second segment group to move in a direction having acomponent perpendicular to the optical axis.

A zooming optical system, an optical apparatus and a method formanufacturing the zooming optical system according to a secondembodiment of the present application will hereinafter be described.

The zooming optical system according to the second embodiment of thepresent application includes, in order from an object side: a first lensgroup having positive refractive power; a second lens group havingnegative refractive power; a third lens group having positive refractivepower; and a fourth lens group having negative refractive power; uponzooming from a wide-angle end state to a telephoto end state, a distancebetween the first lens group and the second lens group, a distancebetween the second lens group and the third lens group and a distancebetween the third lens group and the fourth lens group are respectivelyvaried; the third lens group has, in order from the object side, a firstsegment group having positive refractive power and a second segmentgroup; the second segment group is moved to have a component in adirection perpendicular to the optical axis; and the followingconditional expression (3) is satisfied:2.80<f1/f3<4.50  (3)where f1 denotes a focal length of the first lens group, and f3 denotesa focal length of the third lens group.

The zooming optical system according to the second embodiment of thepresent application, as described above, with the second segment groupin the third lens group being moved to include the component in adirection perpendicular to the optical axis, is thereby enabled tocorrect the image blur caused by the camera shake, i.e., to reduce thevibrations.

The conditional expression (3) described above defines a focal length ofthe first lens group with respect to the focal length of the third lensgroup. The zooming optical system according to the second embodiment ofthe present application satisfies the conditional expression (3) and isthereby enabled to preferably correct the curvature of field in thewide-angle end state, and to preferably correct the spherical aberrationin the telephoto end state.

When the corresponding value of the conditional expression (3) of thezooming optical system according to the second embodiment of the presentapplication exceeds the upper limit value, the zooming effect of thefirst lens group decreases. Therefore, the refractive power of thesecond lens group needs to increase for ensuring the zooming ratio,resulting undesirably in causing the occurrence of the curvature offield in the wide-angle end state and the occurrence of the sphericalaberration in the telephoto end state. Note that the upper limit valueof the conditional expression (3) is set to, more preferably, 4.30 forfurther ensuring the effects of the present application.

Whereas when the corresponding value of the conditional expression (3)of the zooming optical system according to the first embodiment of thepresent application decreases below the lower limit value, therefractive power of the first lens group increases, and it isundesirably difficult to correct the spherical aberration in thetelephoto end state. It is to be noted that the lower limit value of theconditional expression (3) is set to, more preferably, 3.00 for furtherensuring the effects of the present application.

With this configuration described above, it is feasible to realize thecompact zooming optical system having the vibration reduction function,the high zooming ratio, the wide-angle view and the superb opticalperformance.

It is desirable that the second segment group of the zooming opticalsystem according to the second embodiment of the present application hasnegative refractive power. With this configuration, the zooming opticalsystem according to the second embodiment of the present application isscaled down, and it is possible to restrain the variation in the comawhen being eccentric.

Further, it is desirable that the zooming optical system according tothe second embodiment of the present application satisfies the followingconditional expression (4).2.20<f1/f4<3.50  (4)where f1 denotes the focal length of the first lens group, and f4denotes the focal length of the fourth lens group.

The conditional expression (4) defines the focal length of the thirdlens group with respect to the focal length of the fourth lens group.The zooming optical system according to the second embodiment of thepresent application satisfies the conditional expression (4) and isthereby enabled to preferably correct the curvature of field and thecoma in the wide-angle end state, and to preferably correct thespherical aberration in the telephoto end state.

When the corresponding value of the conditional expression (4) of thezooming optical system according to the second embodiment of the presentapplication exceeds the upper limit value, the refractive power of thefourth lens group rises, and it is undesirably difficult to correct thecurvature of field and the coma in the wide-angle end state. Note thatthe upper limit value of the conditional expression (4) is set to, morepreferably, 3.30 for further ensuring the effects of the presentapplication.

Whereas when the corresponding value of the conditional expression (4)of the zooming optical system according to the second embodiment of thepresent application decreases below the lower limit value, therefractive power of the first lens group increases, and it isundesirably difficult to correct the spherical aberration particularlyin the telephoto end state. It is to be noted that the lower limit valueof the conditional expression (4) is set to, more preferably, 2.50 forfurther ensuring the effects of the present application.

Further, in the zooming optical system according to the secondembodiment of the present application, it is desirable that at least apart of the second lens group moves along the optical-axis whenfocusing. The focusing is conducted by at least a part of the compactand light-weight second lens group, whereby the quick focusing can beattained.

Moreover, it is desirable that the zooming optical system according tothe second embodiment of the present application satisfies the followingconditional expression (6).0.35<(−f2)/f3<0.55  (6)where f2 denotes the focal length of the second lens group, and f3denotes the focal length of the third lens group.

The conditional expression (6) defines the focal length of the secondlens group with respect to the focal length of the third lens group. Thezooming optical system according to the second embodiment of the presentapplication satisfies the conditional expression (6) and is therebyenabled to preferably correct the curvature of field in the wide-angleend state, and to preferably correct the spherical aberration in thetelephoto end state.

When the corresponding value of the conditional expression (6) of thezooming optical system according to the second embodiment of the presentapplication exceeds the upper limit value, the zooming effect of thesecond lens group decreases. Therefore, the refractive power of thefirst lens group needs to increase for ensuring the zooming ratio,resulting undesirably in causing the occurrence of the curvature offield in the wide-angle end state and the occurrence of the sphericalaberration in the telephoto end state. Note that the upper limit valueof the conditional expression (6) is set to, more preferably, 0.52 forfurther ensuring the effects of the present application.

Whereas when the corresponding value of the conditional expression (6)of the zooming optical system according to the second embodiment of thepresent application decreases below the lower limit value, the zoomingeffect of the third lens group increases. Hence, the refractive power ofthe first lens group or the second lens group needs to increase forensuring the zooming ratio, resulting undesirably in the difficulty tocorrect the spherical aberration in the telephoto end state and tocorrect the curvature of field in the wide-angle end state. Note thatthe lower limit value of the conditional expression (6) is set to, morepreferably, 0.38 for further ensuring the effects of the presentapplication.

Further, it is desirable that the second segment group of the zoomingoptical system according to the second embodiment of the presentapplication is configured to include the cemented lens having onepositive lens and one negative lens. With this configuration, thedecentering coma can be preferably corrected when moving the secondsegment group to include the component in a direction perpendicular tothe optical axis.

Furthermore, it is desirable that the zooming optical system accordingto the second embodiment of the present application satisfies thefollowing conditional expression (5).0.20<|f32|/f1<0.43  (5)where f1 denotes the focal length of the first lens group, and f32denotes the focal length of the second segment group.

The conditional expression (5) defines the focal length of the secondsegment group with respect to the focal length of the first lens group.The zooming optical system according to the second embodiment of thepresent application satisfies the conditional expression (5) and isthereby enabled to preferably correct the spherical aberration in thetelephoto end state, and to preferably correct the coma when moving thesecond segment group to include the component in a directionperpendicular to the optical axis.

When the corresponding value of the conditional expression (5) of thezooming optical system according to the second embodiment of the presentapplication exceeds the upper limit value, the refractive power of thefirst lens group rises, and it is undesirably difficult to correct thespherical aberration in the telephoto end state. Note that the upperlimit value of the conditional expression (5) is set to, morepreferably, 0.41 for further ensuring the effects of the presentapplication.

Whereas when the corresponding value of the conditional expression (5)of the zooming optical system according to the second embodiment of thepresent application decreases below the lower limit value, therefractive power of the second segment group increases. It is thereforeundesirable to cause deterioration in the coma when moving the secondlens group to include the component in a direction perpendicular to theoptical axis. It is to be noted that the lower limit value of theconditional expression (5) is set to, more preferably, 0.25 for furtherensuring the effects of the present application.

Moreover, it is desirable that the first lens group of the zoomingoptical system according to the second embodiment of the presentapplication moves along the optical axis when zooming to the telephotoend state from the wide-angle end state. With this configuration, therefractive power of each of the respective lens groups relating to thezooming, i.e., of the first to fourth lens groups can be decreased, andit is feasible to ensure the preferable optical performance covering thewide-angle end state and the telephoto end state throughout.

The optical apparatus of the present application is characterized byhaving the zooming optical system configured as described aboveaccording to the second embodiment. This configuration enables theactualization of the compact optical apparatus having the vibrationreduction function, the high zooming ratio, the wide-angle view and thesuperb optical performance.

A method for manufacturing the zooming optical system according to thesecond embodiment of the present application is a method formanufacturing the zooming optical system comprising, in order from anobject side: a first lens group having positive refractive power; asecond lens group having negative refractive power; a third lens grouphaving positive refractive power; and a fourth lens group havingpositive refractive power;

said method comprising steps of

constructing the third lens group to include, in order from the objectside, a first segment group having positive refractive power and asecond segment group,

constructing the first lens group and the third lens group such that thefollowing conditional expression (3) may be satisfied:2.80<f1/f3<4.50  (3)where f1 denotes a focal length of the first lens group, and f3represents a focal length of the third lens group,

constructing such that a distance between the first lens group and thesecond lens group, a distance between the second lens group and thethird lens group and a distance between the third lens group and thefourth lens group respectively varied, upon zooming to the telephoto endstate from the wide-angle end state, and

constructing the second segment group to move in a direction having acomponent perpendicular to the optical axis.

A zooming optical system, an optical apparatus and a method formanufacturing the zooming optical system according to a third embodimentof the present application will hereinafter be described.

The zooming optical system according to the third embodiment of thepresent application includes, in order from an object side: a first lensgroup having positive refractive power; a second lens group havingnegative refractive power; a third lens group having positive refractivepower; and a fourth lens group having negative refractive power; uponzooming from a wide-angle end state to a telephoto end state, a distancebetween the first lens group and the second lens group, a distancebetween the second lens group and the third lens group and a distancebetween the third lens group and the fourth lens group are respectivelyvaried; the third lens group has, in order from the object side, a firstsegment group having positive refractive power and a second segmentgroup; the second segment group is moved to have a component in adirection perpendicular to the optical axis; and the followingconditional expressions (5) and (7) are satisfied:0.20<|f32|/f1<0.43  (5)0.60<f31/f3<0.90  (7)where f1 denotes a focal length of the first lens group, f3 denotes afocal length of the third lens group, f31 denotes a focal length of thefirst segment group, and f32 denotes a focal length of the secondsegment group.

The zooming optical system according to the third embodiment of thepresent application, as described above, with the second segment groupin the third lens group being moved to include the component in adirection perpendicular to the optical axis, is thereby enabled tocorrect the image blur caused by the camera shake, i.e., to reduce thevibrations.

The conditional expression (5) described above defines a focal length ofthe second segment group with respect to the focal length of the firstlens group. The zooming optical system according to the third embodimentof the present application satisfies the conditional expression (5) andis thereby enabled to preferably correct the spherical aberration in thetelephoto end state, and to preferably correct the coma when moving thesecond segment group to include the component in a directionperpendicular to the optical axis.

When the corresponding value of the conditional expression (5) of thezooming optical system according to the third embodiment of the presentapplication exceeds the upper limit value, the refractive power of thefirst lens group rises, and it is undesirably difficult to correct thespherical aberration in the telephoto end state. Note that the upperlimit value of the conditional expression (5) is set to, morepreferably, 0.41 for further ensuring the effects of the presentapplication.

Whereas when the corresponding value of the conditional expression (5)of the zooming optical system according to the third embodiment of thepresent application decreases below the lower limit value, therefractive power of the second segment group increases. It is thereforeundesirable to cause the deterioration in the coma when moving thesecond lens group to include the component in a direction perpendicularto the optical axis. It is to be noted that the lower limit value of theconditional expression (5) is set to, more preferably, 0.25 for furtherensuring the effects of the present application.

The conditional expression (7) defines the focal length of the firstsegment group with respect to the focal length of the third lens group.The zooming optical system according to the third embodiment of thepresent application satisfies the conditional expression (7) and isthereby enabled to preferably correct the spherical aberration in thetelephoto end state, and to preferably correct the curvature of field inthe wide-angle end state.

When the corresponding value of the conditional expression (7) of thezooming optical system according to the third embodiment of the presentapplication exceeds the upper limit value, the refractive power of thethird lens group rises, and it is undesirably difficult to correct thespherical aberration in the telephoto end state. Note that the upperlimit value of the conditional expression (7) is set to, morepreferably, 0.85 for further ensuring the effects of the presentapplication.

Whereas when the corresponding value of the conditional expression (7)of the zooming optical system according to the third embodiment of thepresent application decreases below the lower limit value, the zoomingeffect of the third lens group decreases. Therefore, the refractivepower of the first lens group or the second lens group needs to increasefor ensuring the zooming ratio, resulting undesirably in the difficultyto correct the spherical aberration in the telephoto end state and tocorrect the curvature of field in the wide-angle end state. Note thatthe lower limit value of the conditional expression (7) is set to, morepreferably, 0.65 for further ensuring the effects of the presentapplication.

This configuration enables the actualization of the compact opticalapparatus having the vibration reduction function, the high zoomingratio, the wide-angle view and the superb optical performance.

Further, it is desirable that the second segment group of the zoomingoptical system according to the third embodiment of the presentapplication has negative refractive power. With this configuration, thezooming optical system according to the third embodiment of the presentapplication is scaled down, and it is possible to restrain a variationin the coma when being eccentric.

Furthermore, it is desirable that the zooming optical system accordingto the third embodiment of the present application satisfies thefollowing conditional expression (1).8.00<f1/(−f2)<10.00  (1)where f1 denotes a focal length of the first lens group, and f2 denotesa focal length of the second lens group.

The conditional expression (1) defines the focal length of the firstlens group with respect to the focal length of the second lens group.The zooming optical system according to the third embodiment of thepresent application satisfies the conditional expression (1) and isthereby enabled to preferably correct the curvature of field in thewide-angle end state, and to preferably correct the spherical aberrationin the telephoto end state.

When the corresponding value of the conditional expression (1) of thezooming optical system according to the third embodiment of the presentapplication exceeds the upper limit value, the zooming effect of thefirst lens group decreases. Therefore, the refractive power of thesecond lens group needs to increase for ensuring the zooming ratio,resulting undesirably in causing the occurrence of the curvature offield in the wide-angle end state and the occurrence of the sphericalaberration in the telephoto end state. Note that the upper limit valueof the conditional expression (1) is set to, more preferably, 9.70 forfurther ensuring the effects of the present application.

Whereas when the corresponding value of the conditional expression (1)of the zooming optical system according to the third embodiment of thepresent application decreases below the lower limit value, therefractive power of the first lens group increases, and it isundesirably difficult to correct the spherical aberration in thetelephoto end state. It is to be noted that the lower limit value of theconditional expression (1) is set to, more preferably, 8.10 for furtherensuring the effects of the present application.

Further, it is desirable that at least a part of the second lens groupof the zooming optical system according to the third embodiment of thepresent application moves along the optical-axis when focusing. Thefocusing is conducted by at least a part of the compact and light-weightsecond lens group, whereby the quick focusing can be attained.

Moreover, it is desirable that the zooming optical system according tothe third embodiment of the present application satisfies the followingconditional expression (4).2.20<f1/f4<3.50  (4)where f1 denotes the focal length of the first lens group, and f4denotes the focal length of the fourth lens group.

The conditional expression (4) defines the focal length of the firstlens group with respect to the focal length of the fourth lens group.The zooming optical system according to the third embodiment of thepresent application satisfies the conditional expression (4) and isthereby enabled to well correct the curvature of field and the coma inthe wide-angle end state, and to well correct the spherical aberrationin the telephoto end state.

When the corresponding value of the conditional expression (4) of thezooming optical system according to the third embodiment of the presentapplication exceeds the upper limit value, the refractive power of thefourth lens group rises, and it is undesirably difficult to correct thecurvature of field and the coma in the wide-angle end state. Note thatthe upper limit value of the conditional expression (4) is set to, morepreferably, 3.30 for further ensuring the effects of the presentapplication.

Whereas when the corresponding value of the conditional expression (4)of the zooming optical system according to the third embodiment of thepresent application decreases below the lower limit value, therefractive power of the first lens group increases, resultingundesirably in the difficulty to correct the spherical aberration in thetelephoto end state. Note that the lower limit value of the conditionalexpression (4) is set to, more preferably, 2.50 for further ensuring theeffects of the present application.

Further, it is desirable that the second segment group of the zoomingoptical system according to the third embodiment of the presentapplication is configured to include the cemented lens having onepositive lens and one negative lens. With this configuration, thedecentering coma can be preferably corrected when moving the secondsegment group to include the component in a direction perpendicular tothe optical axis.

Furthermore, it is desirable that the zooming optical system accordingto the third embodiment of the present application satisfies thefollowing conditional expression (2).0.60<f3/f4<0.90  (2)where f3 denotes the focal length of the third lens group, and f4denotes the focal length of the fourth lens group.

The conditional expression (2) defines the focal length of the thirdlens group with respect to the focal length of the fourth lens group.The zooming optical system according to the third embodiment of thepresent application satisfies the conditional expression (2) and isthereby enabled to well correct the curvature of field and the coma inthe wide-angle end state, and to well correct the spherical aberrationin the telephoto end state.

When the corresponding value of the conditional expression (2) of thezooming optical system according to the third embodiment of the presentapplication exceeds the upper limit value, the refractive power of thefourth lens group rises, and it is undesirably difficult to correct thecurvature of field and the coma in the wide-angle end state. Note thatthe upper limit value of the conditional expression (2) is set to, morepreferably, 0.85 for further ensuring the effects of the presentapplication.

Whereas when the corresponding value of the conditional expression (2)of the zooming optical system according to the third embodiment of thepresent application decreases below the lower limit value, therefractive power of the third lens group increases, resultingundesirably in the difficulty to correct the spherical aberrationparticularly in the telephoto end state. It is to be noted that thelower limit value of the conditional expression (2) is set to, morepreferably, 0.65 for further ensuring the effects of the presentapplication.

Moreover, it is desirable that the first lens group of the zoomingoptical system according to the third embodiment of the presentapplication moves along the optical axis when zooming to the telephotoend state from the wide-angle end state. With this configuration, therefractive power of each of the respective lens groups relating to thezooming, i.e., of the first to fourth lens groups can be decreased, andit is feasible to ensure the preferable optical performance covering thewide-angle end state and the telephoto end state throughout.

The optical apparatus of the present application is characterized byhaving the zooming optical system configured as described aboveaccording to the third embodiment. This configuration enables theactualization of the compact optical apparatus having the vibrationreduction function, the high zooming ratio, the wide-angle view and thesuperb optical performance.

A method for manufacturing the zooming optical system according to thethird embodiment of the present application is a method formanufacturing the zooming optical system in order from an object side: afirst lens group having positive refractive power; a second lens grouphaving negative refractive power; a third lens group having positiverefractive power; and a fourth lens group having positive refractivepower;

said method comprising steps of

constructing the third lens group to include, in order from an objectside, a first segment group having positive refractive power and asecond segment group,

constructing the first lens group and the third lens group such that thefollowing conditional expressions (5) and (7) may be satisfied:0.20<|f32|/f1<0.43  (5)0.60<f31/f3<0.90  (7)where f1 denotes a focal length of the first lens group, f3 represents afocal length of the third lens group, f31 denotes a focal length of thefirst segment group, and f32 represents a focal length of the secondsegment group,

constructing such that a distance between the first lens group and thesecond lens group, a distance between the second lens group and thethird lens group and a distance between the third lens group and thefourth lens group respectively varied upon zooming to the telephoto endstate from the wide-angle end state, and

constructing the second segment group to move in a direction having acomponent perpendicular to the optical axis.

The zooming optical systems relating to Examples of numeric valuesaccording to the first to third embodiment of the present applicationwill hereinafter be described based on the accompanying drawings. Itshould be noted that first to sixth Examples are the Examples common tothe first to third embodiments throughout.

First Example

FIGS. 1A, 1B and 1C are sectional views of the zooming optical system inthe wide-angle end state, the intermediate focal length state and thetelephoto end state according to the first Example of the first to thirdembodiments of the present application.

The zooming optical system according to the first Example is configuredto include, in order from an object side, a first lens group G1 havingpositive refractive power, a second lens group G2 having negativerefractive power, a third lens group G3 having positive refractive powerand a fourth lens group G4 having positive refractive power.

The first lens group G1 is configured to include, in order from theobject side, a cemented lens composed of a negative meniscus lens L11with a convex surface directed to the object side and a biconvexpositive lens L12, and a positive meniscus lens L13 with the convexsurface directed to the object side.

The second lens group G2 is configured to include, in order from theobject side, a negative meniscus lens L21 with the convex surfacedirected to the object side, a biconcave negative lens L22, a biconvexpositive lens L23 and a negative meniscus lens L24 with a concavesurface directed to the object side. Note that the negative meniscuslens L21 positioned closest to the object side in the second lens groupG2 is an aspherical lens with an object-sided lens surface beingaspherical.

The third lens group G3 is configured to include, in order from theobject side, a first segment group G31 having positive refractive powerand a second segment group G32 having negative refractive power. Notethat an aperture stop S is provided on the object side of the third lensgroup G3.

The first segment group G31 is configured to include, in order from theobject side, a biconvex positive lens L31, and a cemented lens composedof a biconvex positive lens L32 and a biconcave negative lens L33.

The second segment group G32 is configured to include, in order from theobject side, only a cemented lens composed of a biconcave negative lensL34 and a positive meniscus lens L35 with the convex surface directed tothe object side.

The fourth lens group G4 is configured to include, in order from theobject side, a biconvex positive lens L41, and a cemented lens composedof a positive meniscus lens L42 with a concave surface directed to theobject side and a negative meniscus lens L43 with the concave surfacedirected to the object side. Note that the positive lens L41 positionedclosest to the object side in the fourth lens group G4 is an asphericallens with the object-sided lens surface being aspherical.

Under the construction descried above, in the zooming optical systemaccording to the first Example, when zooming to the telephoto end statefrom the wide-angle end state, the first lens group G1, the third lensgroup G3 and the fourth lens group G4 move toward the object side alongthe optical axis and the second lens group G2 moves along the opticalaxis so that an air distance between the first lens group G1 and thesecond lens group G2 increases, while an air distance between the secondlens group G2 and the third lens group G3 decreases, and an air distancebetween the third lens group G3 and the fourth lens group G4 varies.Note that the aperture stop S moves together with the third lens groupG3 on this occasion.

Further, the zooming optical system according to the first Exampleperforms focusing on a near-distance object from an infinite-distanceobject by moving the second lens group G2 toward the object side alongthe optical axis.

Moreover, the zooming optical system according to the first Examplereduces the vibrations by moving only the second segment group G32 as ananti-vibration lens group so as to include a component in a directionperpendicular to the optical axis when the camera shake (hand vibration)etc is caused.

The following Table 1 shows values of various items of data in the firstExample. In Table 1, the symbol f represents a focal length, and BFdenotes a back focus. In [Surface Data], m represents an optical surfacenumber counted from the object side, r stands for a radius of curvatureof the lens surface, d denotes a surface to surface distance on theoptical axis, nd represents a refractive index with respect to thed-line (λ=587.6 nm), and νd is an Abbe number with respect to the d-line(λ=587.6 nm), respectively. Further, the symbol OP denotes an objectplane, and I represents an image plane, respectively. Note that anexpression “the radius-of-curvature r=∞” implies a plane. Moreover, anaspherical surface is indicated by a surface number attached with a mark“*”, and a paraxial radius of curvature is indicated in a column of theradius of curvature r of the aspherical surface.

In [Aspherical Data], with respect to the aspherical surface shown inthe [Surface Data], an aspherical surface coefficient and a conicconstant are given in the case of expressing a shape of the asphericalsurface.x=(h ² /r)/[1+[1−κ(h/r)²]^(1/2) ]+A4h ⁴ +A6h ⁶ +A8h ⁸ +A10h ¹⁰where h indicates a height in a direction perpendicular to the opticalaxis, x denotes a sag amount defined as a distance along the opticalaxis from a tangential plane of a vertex of the aspherical surface atthe height h up to the aspherical surface, K denotes a conic constant,A4, A6, A8, A10 represent aspherical surface coefficients, and rrepresents a paraxial radius of curvature defined as a radius ofcurvature of a reference spherical surface. It is to be noted that “E-n”(n: integer) represents “×10^(−n)”, and, for example, “1.234E-05”indicates “1.234×10⁻⁵”.

In [Various Data], FNO is an F-number, 2ω is an angle of view (the unitis “°”), Y represents an image height, TL denotes an overall length ofthe zooming optical system, di (i is integer) denotes a variable surfaceto surface from an i-th surface, respectively. Note that W represents awide-angle end state, M denotes an intermediate focal length state, andT denotes a telephoto end state, respectively.

In [Lens Group Data], the symbol ST indicates a starting surface of eachlens group, i.e., a lens surface closest to the object side.

[Values for Conditional Expressions] Shows Corresponding Values in theRespective Conditional Expressions.

Herein, the focal length f, the radius of curvature r and other lengthsdescribed in Table 1 involve using generally “mm” as the unit of thelength. However, the optical system acquires the equal opticalperformance even when proportionally enlarged or reduced and is nottherefore limited to this unit.

It is to be noted that the reference symbols in Table described aboveshall be applied to Tables of the respective Examples.

Herein, in the lens in which f is a focal length of the whole lenssystem, and K is a vibration reduction coefficient, i.e., a ratio of amoving quantity of an image plane I to a moving quantity of theanti-vibration lens group when reducing the vibrations, it may besufficient for correcting a rotating deviation of an angle θ that theanti-vibration lens group is moved by (f·than θ)/κ in the directionperpendicular to the optical axis. Accordingly, in the zooming opticalsystem according to the first Example, in the wide-angle end state, thevibration reduction coefficient is −0.88, and the focal length is 10.0(mm), and hence it follows that the moving quantity of theanti-vibration lens group for correcting the rotating deviation of 1.00°becomes 0.20 (mm). Further, in the telephoto end state, the vibrationreduction coefficient is −1.92, and the focal length is 100.0 (mm), andtherefore it follows that the moving quantity of the anti-vibration lensgroup for correcting the rotating deviation of 0.32° becomes 0.29 (mm).

TABLE 1 First Example [Surface Data] m r d nd vd op ∞ 1 459.647 1.6001.953660 30.27 2 57.423 6.819 1.497820 82.51 3 −154.085 0.100 1.000000 456.956 5.161 1.878896 41.01 5 569.648 d5 1.000000 *6 38.479 1.2001.882991 40.76 7 8.366 3.937 1.000000 8 −16.649 1.200 1.864046 41.96 953.630 0.100 1.000000 10 21.938 3.669 1.846659 23.78 11 −14.738 0.4171.000000 12 −12.219 1.200 1.882997 40.76 13 −43.622 d13 1.000000 14 ∞1.000 1.000000 Aperture Stop S 15 23.408 3.198 1.754999 52.31 16 −31.8800.100 1.000000 17 15.118 3.851 1.497820 82.51 18 −19.673 1.200 1.85644526.89 19 59.726 2.566 1.000000 20 −68.834 1.200 1.822803 45.06 21 7.5533.351 1.878191 37.36 22 24.293 d22 1.000000 *23  16.648 3.632 1.49782082.51 24 −23.750 0.100 1.000000 25 −553.763 4.361 1.577760 40.84 26−8.231 1.200 1.882997 40.76 27 −42.498 BF 1.000000 I ∞ [Aspherical Data]m K A4 A6 A8 A10 6 1 1.54E−05 −2.59E−08  3.23E−10 6.63E−12 23 −0.3689−1.24E−05  6.50E−07 −5.31E−09  1.67E−10 [Various Data] Zooming ratio10.00 W M T f 10.00 50.02 100.00 FNO 3.50 4.80 5.60 2ω 82.49° 18.42°9.30° Y 8.350 8.350 8.350 TL 92.33 135.76 153.35 BF 13.25 39.10 42.51 d52.301 37.043 53.748 d13 19.357 5.095 2.400 d22 6.260 3.363 3.524 [LensGroup Data] ST f G1 1 85.1 G2 6 −9.4 G3 15 21.3 G4 23 28.4 [Values forConditional Expressions] (1)   f1/(−f2) = 9.04 (2) f3/f4 = 0.75 (3)f1/f3 = 3.99 (4) f1/f4 = 3.00 (5) |f32|/f1 = 0.28   (6) (−f2)/f3 =0.44   (7) f31/f3 = 0.75 

FIGS. 2A, 2B and 2C are diagrams of various aberrations when focusing onthe infinite-distance object in the wide-angle end state, theintermediate focal length state and the telephoto end state of thezooming optical system according to the first Example of the presentapplication, respectively.

FIGS. 3A and 3B are a diagram of a meridional transverse aberration whenreducing the vibration against the rotating deviation of 1.00° whenfocusing on the infinite-distance object in the wide-angle end state,and a diagram of the meridional transverse aberration when reducing thevibration against the rotating deviation of 0.32° when focusing on theinfinite-distance object in the telephoto end state of the zoomingoptical system according to the first Example of the presentapplication.

In the respective aberration diagrams, FNO represents the F-number, andY represents the image height, d represents an aberration in the d-line(λ=587.6 nm) and g stands for an aberration in the g-line (λ=435.8 nm),respectively. In a diagram of an astigmatism, a solid line indicates asaggital image surface, and a broken line indicates a meridional imagesurface, respectively. Note that the same reference symbols as those inthe first Example are applied to the aberration diagrams of therespective Examples that will be described later on.

It is understood from the respective aberration diagrams that thezooming optical system according to the first Example preferablycorrects the various aberrations from the wide-angle end state to thetelephoto end state throughout, exhibits excellent image formingperformance and further exhibits the excellent image forming performancewhen reducing the vibrations.

Second Example

FIGS. 4A, 4B and 4C are sectional views of the zooming optical system inthe wide-angle end state, the intermediate focal length state and thetelephoto end state according to a second Example of the first to thirdembodiments of the present application.

The zooming optical system according to the second Example is configuredto include, in order from an object side, a first lens group G1 havingpositive refractive power, a second lens group G2 having negativerefractive power, a third lens group G3 having positive refractive powerand a fourth lens group G4 having positive refractive power.

The first lens group G1 is configured to include, in order from theobject side, a cemented lens composed of a negative meniscus lens L11with the convex surface directed to the object side and a biconvexpositive lens L12, and a positive meniscus lens L13 with the convexsurface directed to the object side.

The second lens group G2 is configured to include, in order from theobject side, a negative meniscus lens L21 with the convex surfacedirected to the object side, a biconcave negative lens L22, a biconvexpositive lens L23 and a negative meniscus lens L24 with the concavesurface directed to the object side. Note that the negative meniscuslens L21 positioned closest to the object side in the second lens groupG2 is an aspherical lens with the object-sided lens surface beingaspherical.

The third lens group G3 is configured to include, in order from theobject side, a first segment group G31 having a positive refractivepower and a second segment group G32 having a negative refractive power.

The first segment group G31 is configured to include, in order from theobject side, a biconvex positive lens L31, and a cemented lens composedof a biconvex positive lens L32 and a biconcave negative lens L33. Notethat an aperture stop S is provided between the positive lens L31 andthe positive lens L32.

The second segment group G32 is configured to include, in order from theobject side, only a cemented lens of a biconcave negative lens L34 and apositive meniscus lens L35 with the convex surface directed to theobject side.

The fourth lens group G4 is configured to include, in order from theobject side, a biconvex positive lens L41, and a cemented lens of abiconvex positive lens L42 and a negative meniscus lens L43 with theconcave surface directed to the object side. Note that the positive lensL41 positioned closest to the object side in the fourth lens group G4 isan aspherical lens with the object-sided lens surface being aspherical.

Under the construction descried above, in the zooming optical systemaccording to the second Example, when zooming to the telephoto end statefrom the wide-angle end state, the first lens group G1, the third lensgroup G3 and the fourth lens group G4 move toward the object side alongthe optical axis, and the second lens group G2 moves along the opticalaxis so that an air distance between the first lens group G1 and thesecond lens group G2 increases, while an air distance between the secondlens group G2 and the third lens group G3 decreases, and an air distancebetween the third lens group G3 and the fourth lens group G4 varies.Note that the aperture stop S moves together with the third lens groupG3 on this occasion.

Further, the zooming optical system according to the second Exampleperforms focusing on the near-distance object from the infinite-distanceobject by moving the second lens group G2 toward the object side alongthe optical axis.

Moreover, the zooming optical system according to the second Examplereduces the vibrations by moving only the second segment group G32 asthe anti-vibration lens group so as to include the component in thedirection perpendicular to the optical axis when the camera shake etc iscaused.

The following Table 2 shows values of various items of data in thesecond Example. Herein, in the zooming optical system according to thesecond Example, in the wide-angle end state, the vibration reductioncoefficient is −0.61, and the focal length is 10.3 (mm), and hence itfollows that the moving quantity of the anti-vibration lens group forcorrecting the rotating deviation of 0.99° becomes 00.28 (mm). Further,in the telephoto end state, the vibration reduction coefficient is−1.42, and the focal length is 97.0 (mm), and therefore it follows thatthe moving quantity of the anti-vibration lens group for correcting therotating deviation of 0.32° becomes 0.38 (mm).

TABLE 2 Second Example [Surface Data] m r d nd vd op ∞ 1 214.935 1.6001.953660 30.27 2 60.293 6.140 1.497820 82.51 3 −216.386 0.100 1.000000 459.192 4.825 1.810230 46.17 5 516.132 d5 1.000000 *6 32.741 1.2001.882997 40.76 7 8.577 4.007 1.000000 8 −15.726 1.200 1.839050 43.75 946.418 0.100 1.000000 10 21.908 3.623 1.846660 23.78 11 −16.185 0.6011.000000 12 −11.861 1.200 1.882997 40.76 13 −33.094 d13 1.000000 1424.800 2.781 1.754999 52.31 15 −39.736 0.500 1.000000 16 ∞ 1.6001.000000 Aperture Stop S 17 14.646 3.397 1.497820 82.51 18 −19.677 1.2001.852045 25.40 19 69.922 2.144 1.000000 20 −879.676 1.200 1.802688 46.8721 8.771 2.765 1.876437 36.60 22 23.971 d22 1.000000 *23  17.538 3.3821.497820 82.51 24 −22.122 0.100 1.000000 25 712.073 4.071 1.625207 37.1426 −8.262 1.200 1.882997 40.76 27 −97.309 BF 1.000000 I ∞ [AsphericalData] m K A4 A6 A8 A10 6 1 1.66E−05 1.53E−07 −4.44E−09 5.56E−11 23 1−5.70E−05  6.19E−07 [Various Data] Zooming ratio 9.42 W M T f 10.3049.99 96.98 FNO 3.50 5.20 5.67 2ω 79.71° 17.90° 9.37° Y 8.190 8.1908.190 TL 89.39 132.08 150.34 BF 13.54 36.00 44.01 d5 2.317 38.392 51.572d13 18.962 5.444 2.400 d22 5.643 3.306 3.427 [Lens Group Data] ST f G1 186.9 G2 6 −9.6 G3 14 21.2 G4 23 31.0 [Values for ConditionalExpressions] (1)   f1/(−f2) = 9.09 (2) f3/f4 = 0.69 (3) f1/f3 = 4.10 (4)f1/f4 = 2.81 (5) |f32|/f1 = 0.40   (6) (−f2)/f3 = 0.45   (7) f31/f3 =0.82 

FIGS. 5A, 5B and 5C are diagrams of various aberrations when focusing onthe infinite-distance object in the wide-angle end state, theintermediate focal length state and the telephoto end state of thezooming optical system according to the second Example of the presentapplication, respectively.

FIGS. 6A and 6B are a diagram of a meridional transverse aberration whenreducing the vibration against the rotating deviation of 0.99° whenfocusing on the infinite-distance object in the wide-angle end state,and a diagram of the meridional transverse aberration when reducing thevibration against the rotating deviation of 0.32° when focusing on theinfinite-distance object in the telephoto end state, of the zoomingoptical system according to the second Example of the presentapplication.

It is understood from the respective aberration diagrams that thezooming optical system according to the second Example corrects well thevarious aberrations from the wide-angle end state to the telephoto endstate throughout, exhibits excellent image forming performance andfurther exhibits the excellent image forming performance when reducingthe vibrations.

Third Example

FIGS. 7A, 7B and 7C are sectional views of the zooming optical system inthe wide-angle end state, the intermediate focal length state and thetelephoto end state according to a third Example of the first to thirdembodiments of the present application.

The zooming optical system according to the third Example is configuredto include, in order from an object side, a first lens group G1 havingpositive refractive power, a second lens group G2 having negativerefractive power, a third lens group G3 having positive refractive powera the fourth lens group G4 having positive refractive power.

The first lens group G1 is configured to include, in order from theobject side, a cemented lens composed of a negative meniscus lens L11with the convex surface directed to the object side and a biconvexpositive lens L12, and a positive meniscus lens L13 with the convexsurface directed to the object side.

The second lens group G2 is configured to include, in order from theobject side, a negative meniscus lens L21 with the convex surfacedirected to the object side, a biconcave negative lens L22, a biconvexpositive lens L23 and a negative meniscus lens L24 with the concavesurface directed to the object side. Note that the negative meniscuslens L21 positioned closest to the object side in the second lens groupG2 is an aspherical lens with the object-sided lens surface beingaspherical.

The third lens group G3 is configured to include, in order from theobject side, a first segment group G31 having positive refractive powerand a second segment group G32 having negative refractive power.

The first segment group G31 is configured to include, in order from theobject side, a biconvex positive lens L31, and a cemented lens composedof a biconvex positive lens L32 and a biconcave negative lens L33. Notethat an aperture stop S is provided between the positive lens L31 andthe positive lens L32.

The second segment group G32 is configured to include, in order from theobject side, only a cemented lens composed of a biconcave negative lensL34 and a positive meniscus lens L35 with the convex surface directed tothe object side.

The fourth lens group G4 is configured to include, in order from theobject side, a biconvex positive lens L41, and a cemented lens composedof a biconvex positive lens L42 and a negative meniscus lens L43 withthe concave surface directed to the object side. Note that the positivelens L41 positioned closest to the object side in the fourth lens groupG4 is an aspherical lens with the object-sided lens surface beingaspherical.

Under the construction descried above, in the zooming optical systemaccording to the third Example, when zooming to the telephoto end statefrom the wide-angle end state, the first lens group G1, the third lensgroup G3 and the fourth lens group G4 move toward the object side alongthe optical axis, and the second lens group G2 moves along the opticalaxis so that an air distance between the first lens group G1 and thesecond lens group G2 increases, while an air distance between the secondlens group G2 and the third lens group G3 decreases, and an air distancebetween the third lens group G3 and the fourth lens group G4 varies.Note that the aperture stop S moves together with the third lens groupG3 on this occasion.

Further, the zooming optical system according to the third Exampleperforms focusing on the near-distance object from the infinite-distanceobject by moving the second lens group G2 toward the object side alongthe optical axis.

Moreover, the zooming optical system according to the third Examplereduces the vibrations by moving only the second segment group G32 asthe anti-vibration lens group so as to include the component in thedirection perpendicular to the optical axis when the camera shake etc iscaused.

The following Table 3 shows values of various items of data in the thirdExample. Herein, in the zooming optical system according to the thirdExample, in the wide-angle end state, the vibration reductioncoefficient is −0.79, and the focal length is 10.3 (mm), and hence itfollows that the moving quantity of the anti-vibration lens group forcorrecting the rotating deviation of 0.60° becomes 00.14 (mm). Further,in the telephoto end state, the vibration reduction coefficient is−1.74, and the focal length is 97.0 (mm), and therefore it follows thatthe moving quantity of the anti-vibration lens group for correcting therotating deviation of 0.19° becomes 0.19 (mm).

TABLE 3 Third Example [Surface Data] m r d nd vd op ∞ 1 167.891 1.6001.950000 29.37 2 69.549 5.925 1.497820 82.51 3 −183.905 0.100 1.000000 456.184 4.388 1.729157 54.66 5 198.836 d5 1.000000 *6 41.829 1.2001.882997 40.76 7 8.946 3.756 1.000000 8 −17.431 1.200 1.864742 41.92 938.456 0.100 1.000000 10 20.545 3.705 1.846660 23.78 11 −15.937 0.6291.000000 12 −11.749 1.200 1.882997 40.76 13 −35.044 d13 1.000000 1424.738 2.730 1.754999 52.31 15 −36.975 0.500 1.000000 16 ∞ 1.6001.000000 Aperture Stop S 17 14.497 3.278 1.497820 82.51 18 −19.591 1.2001.851149 25.12 19 97.099 2.184 1.000000 20 −105.628 1.200 1.875733 41.2121 8.299 2.780 1.939960 33.32 22 26.001 d22 1.000000 *23  20.461 3.2051.497820 82.51 24 −22.765 0.100 1.000000 25 175.793 3.930 1.616359 38.3226 −9.172 1.200 1.883682 40.65 27 −65.712 BF 1.000000 I ∞ [AsphericalData] m K A4 A6 A8 A10 6 1 1.28E−05 5.16E−08 −8.45E−10 2.36E−11 23 1−5.71E−05  2.70E−07 [Various Data] Zooming ratio 9.42 W M T f 10.3050.00 97.00 FNO 3.50 5.20 5.60 2ω 79.71° 17.90° 9.37° Y 8.190 8.1908.190 TL 89.38 132.39 150.35 BF 14.01 36.64 44.30 d5 2.319 39.217 52.463d13 19.087 5.422 2.400 d22 6.245 3.394 3.481 [Lens Group Data] ST f G1 188.3 G2 6 −9.4 G3 14 21.1 G4 23 28.4 [Values for ConditionalExpressions] (1)   f1/(−f2) = 9.41 (2) f3/f4 = 0.74 (3) f1/f3 = 4.18 (4)f1/f4 = 3.11 (5) |f32|/f1 = 0.31   (6) (−f2)/f3 = 0.44   (7) f31/f3 =0.77 

FIGS. 8A, 8B and 8C are diagrams of various aberrations when focusing onthe infinite-distance object in the wide-angle end state, theintermediate focal length state and the telephoto end state of thezooming optical system according to the third Example of the presentapplication, respectively.

FIGS. 9A and 9B are, respectively, a diagram of a meridional transverseaberration when reducing the vibration against the rotating deviation of0.60° when focusing on the infinite-distance object in the wide-angleend state, and a diagram of the meridional transverse aberration whenreducing the vibration against the rotating deviation of 0.19° whenfocusing on the infinite-distance object in the telephoto end state, ofthe zooming optical system according to the third Example of the presentapplication.

It is understood from the respective aberration diagrams that thezooming optical system according to the third Example preferablycorrects various aberrations from the wide-angle end state to thetelephoto end state throughout, exhibits excellent image formingperformance and further exhibits excellent image forming performancewhen reducing the vibrations.

Fourth Example

FIGS. 10A, 10B and 10C are sectional views of the zooming optical systemin the wide-angle end state, the intermediate focal length state and thetelephoto end state according to a fourth Example of the first to thirdembodiments of the present application.

The zooming optical system according to the fourth Example is configuredto include, in order from an object side, a first lens group G1 havingpositive refractive power, a second lens group G2 having negativerefractive power, a third lens group G3 having positive refractive powerand a fourth lens group G4 having positive refractive power.

The first lens group G1 is configured to include, in order from theobject side, a cemented lens composed of a negative meniscus lens L11with the convex surface directed to the object side and a biconvexpositive lens L12, and a positive meniscus lens L13 with the convexsurface directed to the object side.

The second lens group G2 is configured to include, in order from theobject side, a negative meniscus lens L21 with the convex surfacedirected to the object side, a biconcave negative lens L22, a biconvexpositive lens L23 and a negative meniscus lens L24 with the concavesurface directed to the object side. Note that the negative meniscuslens L21 positioned closest to the object side in the second lens groupG2 is an aspherical lens with the object-sided lens surface beingaspherical.

The third lens group G3 is configured to include, in order from theobject side, a first segment group G31 having positive refractive powerand a second segment group G32 having negative refractive power.

The first segment group G31 is configured to include, in order from theobject side, a biconvex positive lens L31, and a cemented lens composedof a biconvex positive lens L32 and a biconcave negative lens L33. Notethat the aperture stop S is provided between the positive lens L31 andthe positive lens L32.

The second segment group G32 is configured to include, in order from theobject side, only a cemented lens composed of a biconcave negative lensL34 and a positive meniscus lens L35 with the convex surface directed tothe object side.

The fourth lens group G4 is configured to include, in order from theobject side, a biconvex positive lens L41, and a cemented lens composedof a biconvex positive lens L42 and a negative meniscus lens L43 withthe concave surface directed to the object side. Note that the positivelens L41 positioned closest to the object side in the fourth lens groupG4 is an aspherical lens with the object-sided lens surface beingaspherical.

Under the construction descried above, in the zooming optical systemaccording to the fourth Example, when zooming to the telephoto end statefrom the wide-angle end state, the first lens group G1, the third lensgroup G3 and the fourth lens group G4 move toward the object side alongthe optical axis, and the second lens group G2 moves along the opticalaxis so that an air distance between the first lens group G1 and thesecond lens group G2 increases, while an air distance between the secondlens group G2 and the third lens group G3 decreases, and an air distancebetween the third lens group G3 and the fourth lens group G4 varies.Note that the aperture stop S moves together with the third lens groupG3 on this occasion.

Further, the zooming optical system according to the fourth Exampleperforms focusing on the near-distance object from the infinite-distanceobject by moving the second lens group G2 toward the object side alongthe optical axis.

Moreover, the zooming optical system according to the fourth Examplereduces the vibrations by moving only the second segment group G32 asthe anti-vibration lens group so as to include the component in thedirection perpendicular to the optical axis when the camera shake etc iscaused.

The following Table 4 shows values of various items of data in thefourth Example. Herein, in the zooming optical system according to thefourth Example, in the wide-angle end state, the vibration reductioncoefficient is −0.75, and the focal length is 10.3 (mm), and hence itfollows that the moving quantity of the anti-vibration lens group forcorrecting the rotating deviation of 0.60° becomes 00.14 (mm). Further,in the telephoto end state, the vibration reduction coefficient is−1.62, and the focal length is 97.0 (mm), and therefore it follows thatthe moving quantity of the anti-vibration lens group for correcting therotating deviation of 0.19° becomes 0.20 (mm).

TABLE 4 Fourth Example [Surface Data] m r d nd vd op ∞ 1 134.035 1.6001.995973 28.75 2 56.255 5.824 1.497820 82.51 3 −238.373 0.100 1.000000 450.086 4.577 1.772927 50.05 5 242.611 d5 1.000000 *6 57.243 1.2001.878662 37.67 7 8.942 3.645 1.000000 8 −17.572 1.200 1.882997 40.76 943.025 0.100 1.000000 10 20.980 3.779 1.810399 22.65 11 −15.077 0.5801.000000 12 −11.668 1.200 1.882997 40.76 13 −30.843 d13 1.000000 1422.438 2.768 1.754910 52.33 15 −41.025 0.500 1.000000 16 ∞ 1.6001.000000 Aperture Stop S 17 14.301 3.206 1.497820 82.51 18 −21.553 1.2001.970527 23.71 19 96.060 2.155 1.000000 20 −149.641 1.200 1.882794 40.6121 10.106 2.398 2.002300 28.33 22 24.619 d22 1.000000 *23  20.677 3.1841.593190 67.90 24 −23.793 0.100 1.000000 25 610.600 3.859 1.605665 39.9126 −8.915 1.200 1.890148 39.59 27 −90.902 BF 1.000000 I ∞ [AsphericalData] m K A4 A6 A8 A10 6 1 1.55E−05 −9.41E−08  2.04E−09 −1.22E−12 23 1−4.75E−05  3.47E−07 [Various Data] Zooming ratio 9.42 W M T f 10.3050.00 97.01 FNO 3.50 5.20 5.60 2ω 79.71° 17.90° 9.37° Y 8.190 8.1908.190 TL 89.33 125.89 140.87 BF 14.18 36.03 42.68 d5 2.328 33.549 45.003d13 19.446 5.642 2.400 d22 6.199 3.500 3.615 [Lens Group Data] ST f G1 176.4 G2 6 −9.3 G3 14 21.8 G4 23 28.5 [Values for ConditionalExpressions] (1)   f1/(−f2) = 8.25 (2) f3/f4 = 0.76 (3) f1/f3 = 3.51 (4)f1/f4 = 2.68 (5) |f32|/f1 = 0.38   (6) (−f2)/f3 = 0.43  (7) f31/f3 =0.78 

FIGS. 11A, 11B and 11C are diagrams of various aberrations when focusingon the infinite-distance object in the wide-angle end state, theintermediate focal length state and the telephoto end state of thezooming optical system according to the fourth Example of the presentapplication, respectively.

FIGS. 12A and 12B are, respectively, a diagram of a meridionaltransverse aberration when reducing the vibration against the rotatingdeviation of 0.60° when focusing on the infinite-distance object in thewide-angle end state, and a diagram of the meridional transverseaberration when reducing the vibration against the rotating deviation of0.19° when focusing on the infinite-distance object in the telephoto endstate, of the zooming optical system according to the fourth Example ofthe present application.

It is understood from the respective aberration diagrams that thezooming optical system according to the fourth Example corrects well thevarious aberrations from the wide-angle end state to the telephoto endstate throughout, exhibits excellent image forming performance andfurther exhibits excellent image forming performance when reducing thevibrations.

Fifth Example

FIGS. 13A, 13B and 13C are sectional views of the zooming optical systemin the wide-angle end state, the intermediate focal length state and thetelephoto end state according to a fifth Example of the first to thirdembodiments of the present application.

The zooming optical system according to the fifth Example is configuredto include, in order from an object side, a first lens group G1 havingpositive refractive power, a second lens group G2 having negativerefractive power, a third lens group G3 having positive refractive powerand a fourth lens group G4 having positive refractive power.

The first lens group G1 is configured to include, in order from theobject side, a cemented lens composed of a negative meniscus lens L11with the convex surface directed to the object side and the biconvexpositive lens L12, and a positive meniscus lens L13 with the convexsurface directed to the object side.

The second lens group G2 is configured to include, in order from theobject side, a negative meniscus lens L21 with the convex surfacedirected to the object side, a biconcave negative lens L22, a biconvexpositive lens L23 and a negative meniscus lens L24 with the concavesurface directed to the object side. Note that the negative meniscuslens L21 positioned closest to the object side in the second lens groupG2 is an aspherical lens with the object-sided lens surface beingaspherical.

The third lens group G3 is configured to include, in order from theobject side, a first segment group G31 having positive refractive power,a second segment group G32 having negative refractive power and a thirdsegment group G33 having the negative refractive power.

The first segment group G31 is configured to include, in order from theobject side, a biconvex positive lens L31, and a cemented lens composedof a biconvex positive lens L32 and a negative meniscus lens L33 withthe concave surface directed to the object side. Note that an aperturestop S is provided between the positive lens L31 and the positive lensL32.

The second segment group G32 is configured to include, in order from theobject side, only a cemented lens of a biconcave negative lens L34 and apositive meniscus lens L35 with the convex surface directed to theobject side.

The third segment group G33 is configured to include only a biconcavenegative lens L36.

The fourth lens group G4 is configured to include, in order from theobject side, a biconvex positive lens L41, and a cemented lens composedof a positive meniscus lens L42 with the concave surface directed to theobject side and a negative meniscus lens L43 with the concave surfacedirected to the object side. Note that the positive lens L41 positionedclosest to the object side in the fourth lens group G4 is an asphericallens with the object-sided lens surface being aspherical.

Under the construction descried above, in the zooming optical systemaccording to the fifth Example, when zooming to the telephoto end statefrom the wide-angle end state, the first lens group G1, the third lensgroup G3 and the fourth lens group G4 move toward the object side alongthe optical axis, and the second lens group G2 moves along the opticalaxis so that an air distance between the first lens group G1 and thesecond lens group G2 increases, while an air distance between the secondlens group G2 and the third lens group G3 decreases, and an air distancebetween the third lens group G3 and the fourth lens group G4 varies.Note that the aperture stop S moves together with the third lens groupG3 on this occasion.

Further, the zooming optical system according to the fifth Exampleperforms focusing on the near-distance object from the infinite-distanceobject by moving the second lens group G2 toward the object side alongthe optical axis.

Moreover, the zooming optical system according to the fifth Examplereduces the vibrations by moving only the second segment group G32 asthe anti-vibration lens group so as to include the component in thedirection perpendicular to the optical axis when the camera shake etc iscaused.

The following Table 5 shows values of various items of data in the fifthExample. Herein, in the zooming optical system according to the fifthExample, in the wide-angle end state, the vibration reductioncoefficient is −0.67, and the focal length is 10.3 (mm), and hence itfollows that the moving quantity of the anti-vibration lens group forcorrecting the rotating deviation of 0.60° becomes 00.16 (mm). Further,in the telephoto end state, the vibration reduction coefficient is−1.45, and the focal length is 97.0 (mm), and therefore it follows thatthe moving quantity of the anti-vibration lens group for correcting therotating deviation of 0.19° becomes 0.23 (mm).

TABLE 5 Fifth Example [Surface Data] m r d nd vd op ∞ 1 121.433 1.6002.000942 28.06 2 56.973 5.569 1.497820 82.51 3 −262.775 0.100 1.000000 450.394 4.472 1.757194 52.03 5 230.587 d5 1.000000 *6 60.994 1.2001.874937 35.34 7 8.965 3.574 1.000000 8 −18.928 1.200 1.882997 40.76 940.750 0.100 1.000000 10 20.638 3.681 1.831265 21.76 11 −16.433 0.5391.000000 12 −12.501 1.200 1.882997 40.76 13 −37.209 d13 1.000000 1422.437 2.755 1.747287 52.75 15 −40.608 0.500 1.000000 16 ∞ 1.6001.000000 Aperture Stop S 17 14.529 3.193 1.497820 82.51 18 −21.393 1.2001.959603 22.45 19 −244.270 2.040 1.000000 20 −109.243 1.200 1.88299740.76 21 11.581 2.339 1.964773 29.62 22 31.145 1.462 1.000000 23 −57.1661.000 1.875553 35.71 24 96.176 d24 1.000000 *25  19.938 3.197 1.59319067.90 26 −24.778 0.100 1.000000 27 −825.810 3.984 1.614364 38.61 28−8.826 1.200 1.891733 39.34 29 −44.568 BF 1.000000 I ∞ [Aspherical Data]m K A4 A6 A8 A10 6 1 1.18E−05 −7.24E−08  6.90E−10 5.95E−12 25 1−6.37E−05  4.69E−07 [Various Data] Zooming ratio 9.42 W M T f 10.3050.00 97.00 FNO 3.50 5.20 5.59 2ω 79.72° 18.05° 9.42° Y 8.190 8.1908.190 TL 89.33 125.73 140.86 BF 13.31 35.58 42.88 d5 2.329 33.140 44.235d13 19.776 5.702 2.400 d24 4.905 2.300 2.341 [Lens Group Data] ST f G1 175.9 G2 6 −9.2 G3 14 20.7 G4 25 23.8 [Values for ConditionalExpressions] (1)   f1/(−f2) = 8.24  (2) f3/f4 = 0.87 (3) f1/f3 = 3.66(4) f1/f4 = 3.19 (5) |f32|/f1 = 0.41   (6) (−f2)/f3 = 0.44  (7) f31/f3 =0.71 

FIGS. 14A, 14B and 14C are diagrams of various aberrations when focusingon the infinite-distance object in the wide-angle end state, theintermediate focal length state and the telephoto end state of thezooming optical system according to the fifth Example of the presentapplication, respectively.

FIGS. 15A and 15B are, respectively, a diagram of a meridionaltransverse aberration when reducing the vibration against the rotatingdeviation of 0.600 when focusing on the infinite-distance object in thewide-angle end state, and a diagram of the meridional transverseaberration when reducing the vibration against the rotating deviation of0.19° when focusing on the infinite-distance object in the telephoto endstate of the zooming optical system according to the fifth Example ofthe present application.

It is understood from the respective aberration diagrams that thezooming optical system according to the fifth Example corrects wellvarious aberrations from the wide-angle end state to the telephoto endstate throughout, exhibits excellent image forming performance andfurther exhibits excellent image forming performance when reducing thevibrations.

Sixth Example

FIGS. 16A, 16B and 16C are sectional views of the zooming optical systemin the wide-angle end state, the intermediate focal length state and thetelephoto end state according to a sixth Example of the first to thirdembodiments of the present application.

The zooming optical system according to the sixth Example is configuredto include, in order from an object side, a first lens group G1 havingpositive refractive power, a second lens group G2 having negativerefractive power, a third lens group G3 having positive refractivepower, a fourth lens group G4 having positive refractive power and afifth lens group G5 having negative refractive power.

The first lens group G1 is configured to include, in order from theobject side, a cemented lens composed of a negative meniscus lens L11with the convex surface directed to the object side and a biconvexpositive lens L12, and a positive meniscus lens L13 with the convexsurface directed to the object side.

The second lens group G2 is configured to include, in order from theobject side, a negative meniscus lens L21 with the convex surfacedirected to the object side, a biconcave negative lens L22, a biconvexpositive lens L23 and a negative meniscus lens L24 with the concavesurface directed to the object side. Note that the negative meniscuslens L21 positioned closest to the object side in the second lens groupG2 is an aspherical lens with the object-sided lens surface beingaspherical.

The third lens group G3 is configured to include, in order from theobject side, a first segment group G31 having positive refractive powerand a second segment group G32 having negative refractive power.

The first segment group G31 is configured to include, in order from theobject side, a biconvex positive lens L31, and a cemented lens composedof a biconvex positive lens L32 and a biconcave negative lens L33. Notethat an aperture stop S is provided between the positive lens L31 andthe positive lens L32.

The second segment group G32 is configured to include, in order from theobject side, only a cemented lens composed of a biconcave negative lensL34 and a positive meniscus lens L35 with the convex surface directed tothe object side.

The fourth lens group G4 is configured to include only a biconvexpositive lens L41. Note that the positive lens L41 is an aspherical lenswith the object-sided lens surface being aspherical.

The fifth lens group G5 is configured to include, in order from theobject side, only a cemented lens composed of a positive meniscus lensL51 with the concave surface directed to the object side and a negativemeniscus lens L52 with the concave surface directed to the object side.

Under the construction descried above, in the zooming optical systemaccording to the sixth Example, when zooming to the telephoto end statefrom the wide-angle end state, the first lens group G1, the third lensgroup G3, the fourth lens group G4 and the fifth lens group G5 movetoward the object side along the optical axis, and the second lens groupG2 moves along the optical axis so that an air distance between thefirst lens group G1 and the second lens group G2 increases, an airdistance between the second lens group G2 and the third lens group G3decreases, an air distance between the third lens group G3 and thefourth lens group G4 decreases, and an air distance between the fourthlens group G4 and the fifth lens group G5 increases. Note that theaperture stop S moves together with the third lens group G3 on thisoccasion.

Further, the zooming optical system according to the sixth Exampleperforms focusing on the near-distance object from the infinite-distanceobject by moving the second lens group G2 toward the object side alongthe optical axis.

Moreover, the zooming optical system according to the sixth Examplereduces the vibrations by moving only the second segment group G32 asthe anti-vibration lens group so as to include the component in thedirection perpendicular to the optical axis when the camera shake etc iscaused.

The following Table 6 shows values of various items of data in the sixthExample. Herein, in the zooming optical system according to the sixthExample, in the wide-angle end state, the vibration reductioncoefficient is −0.67, and the focal length is 10.3 (mm), and hence itfollows that the moving quantity of the anti-vibration lens group forcorrecting the rotating deviation of 0.60° becomes 00.16 (mm). Further,in the telephoto end state, the vibration reduction coefficient is−1.48, and the focal length is 97.0 (mm), and therefore it follows thatthe moving quantity of the anti-vibration lens group for correcting therotating deviation of 0.19° becomes 0.22 (mm).

TABLE 6 Sixth Example [Surface Data] m r d nd vd op ∞ 1 130.000 1.6001.977550 30.05 2 53.215 5.870 1.497820 82.51 3 −301.577 0.100 1.000000 449.766 4.706 1.762484 51.33 5 285.082 d5 1.000000 *6 55.053 1.2001.875647 35.77 7 8.920 3.605 1.000000 8 −18.863 1.200 1.882997 40.76 938.238 0.100 1.000000 10 20.860 3.659 1.830156 21.81 11 −16.640 0.6111.000000 12 −12.286 1.200 1.882997 40.76 13 −32.821 d13 1.000000 1422.276 2.832 1.723962 54.17 15 −39.179 0.500 1.000000 16 ∞ 1.6001.000000 Aperture Stop S 17 14.822 3.235 1.497820 82.51 18 −21.400 1.2001.966413 23.23 19 294.782 2.124 1.000000 20 −97.585 1.200 1.881100 39.3521 10.629 2.457 1.993396 28.92 22 30.804 d22 1.000000 *23  24.645 2.8161.593190 67.90 24 −36.143 d24 1.000000 25 −1303.485 3.950 1.602810 40.3626 −8.782 1.200 1.897219 38.51 27 −45.532 BF 1.000000 I ∞ [AsphericalData] m K A4 A6 A8 A10 6 1 1.59E−05 −5.02E−08 1.14E−10 9.01E−12 23 1−4.32E−05  2.52E−07 [Various Data] Zooming ratio 9.42 W M T f 10.3050.00 97.00 FNO 3.50 5.17 5.63 2ω 79.71° 18.02° 9.43° Y 8.190 8.1908.190 TL 89.33 125.31 140.86 BF 13.25 33.66 41.71 d5 2.328 34.196 44.867d13 19.888 5.725 2.400 d22 6.801 3.500 3.502 d24 0.100 1.265 1.411 [LensGroup Data] ST f G1 1 77.2 G2 6 −9.3 G3 14 20.3 G4 23 25.1 G5 25 −72.1[Values for Conditional Expressions] (1)   f1/(−f2) = 8.34 (2) f3/f4 =0.82 (3) f1/f3 = 3.76 (4) f1/f4 = 3.07 (5) |f32|/f1 = 0.42   (6)(−f2)/f3 = 0.45  (7) f31/f3 = 0.79 

FIGS. 17A, 17B and 17C are diagrams of various aberrations when focusingon the infinite-distance object in the wide-angle end state, theintermediate focal length state and the telephoto end state of thezooming optical system according to the sixth Example of the presentapplication, respectively.

FIGS. 18A and 18B are, respectively, a diagram of a meridionaltransverse aberration when reducing the vibration against the rotatingdeviation of 0.60° when focusing on the infinite-distance object in thewide-angle end state, and a diagram of the meridional transverseaberration when reducing the vibration against the rotating deviation of0.19° when focusing on the infinite-distance object in the telephoto endstate of the zooming optical system according to the sixth Example ofthe present application.

It is understood from the respective aberration diagrams that thezooming optical system according to the sixth Example corrects well thevarious aberrations from the wide-angle end state to the telephoto endstate throughout, exhibits excellent image forming performance andfurther exhibits excellent image forming performance when reducing thevibrations.

According to the respective Examples, it is feasible to realize thecompact and light-weight zooming optical system having the vibrationreduction function, an approximately 10-fold high zooming ratio and awide view angle being 70° or larger in the telephoto end state andexhibiting the superb optical performance. It should be noted that eachof the Examples is given by way of a concrete example of the inventionof the present application, and the invention of the present applicationis not limited to these Examples.

The following contents can be properly adopted within the range thatdoes not deteriorate the optical performance of the zooming opticalsystems according to the first to third embodiments of the presentapplication.

The 4-lens-group configuration and the 5-lens-group configuration havebeen exemplified by way of the Examples of the numeric values of thezooming optical systems according to the first to third embodiments ofthe present application, however, the present application not beinglimited to these configurations, and, for example, the zooming opticalsystems taking other lens group configurations such as a 6-lens-groupconfiguration can be configured. To be specific, any inconvenience maynot be caused by taking a configuration of adding a lens or a lens groupon the side closest to the object and on the side closest to the imageof the zooming optical system according to each of the first to thirdembodiments of the present application. It should be noted that the lensgroup connotes a unit having at least one lens separated from other lensgroups through an air distance varying when zooming.

The zooming optical system according to each of the first to thirdembodiments of the present application may be configured to move a partof the lens group, one entire lens group and the plurality of lens groupas the focusing lens group in order to focus on the near-distance objectfrom the infinite-distance object. In particular, it is preferable thatat least a part of the second lens group is formed as the focusing lensgroup. Further, such a focusing lens group can be applied to autofocusing and is also suited to driving by a motor, e.g., an ultrasonicmotor for the auto focusing.

Moreover, the zooming optical system according to each of the first tothird embodiments of the present application can be also configured sothat the whole or a part of any one of the lens groups is moved as theanti-vibration lens group so as to include the component in a directionperpendicular to the optical axis, or is rotationally moved, i.e.,swayed in an intra-plane direction containing the optical axis, therebycorrecting the image blur caused by the camera shake etc. Particularlyin the zooming optical system according to each of the first to thirdembodiments of the present application, it is preferable that at least apart of the third lens group is formed as the anti-vibration lens group.

Further, the lens surface of each of the lenses configuring the zoomingoptical system according to each of the first to third embodiments ofthe present application may be formed as a spherical surface or a flatsurface or an aspherical surface. A case that the lens surface is thespherical surface or the flat surface facilitates lens machining and anassembly adjustment and is preferable because of preventing the opticalperformance from being deteriorated due to an error of the lensmachining and the assembly adjustment. Furthermore, the case ispreferable since even if the image plane deviates, deterioration inimage performance is small. Moreover, if the lens surface is theaspherical surface, it may be sufficient that the lens surface is formedas any one of an aspherical surface based on the cutting work, a glassmold aspherical surface formed by molding a glass in an aspherical shapeand a composite aspherical surface formed by coating a resin over thesurface of the glass in the aspherical shape. Further, the lens surfacemay be formed as a diffraction surface, and the lens may be formed as arefractive index distribution type lens (GRIN (GRadient INdex) lens) ora plastic lens.

It is preferable in the zooming optical system according to each of thefirst to third embodiments of the present application that the aperturestop is disposed between the second lens group and the third lens groupor within the third lens group, and an available configuration is that alens frame substitutes for a role of the aperture stop without providinga member as the aperture stop.

Furthermore, the lens surface of each of the lenses configuring thezooming optical system according to each of the first to thirdembodiments of the present application may be coated with ananti-reflection film having a high transmittance in a broad wave range.With this configuration, it is feasible to reduce a flare and ghost andto attain the high optical performance with the high contrast.

Moreover, in the zooming optical system according to each of the firstto third embodiments of the present application, the zooming ratioranges from about 3 to about 20.

Next, a camera equipped with the zooming optical system according toeach of the first to third embodiments of the present application willbe described based on FIG. 19 .

FIG. 19 is a view showing a configuration of the camera equipped withthe zooming optical system according to each of the first to thirdembodiments of the present application.

A camera 1 is a digital single lens reflex camera equipped with thezooming optical system according to the first Example as an imaging lens2.

In the camera 1, a light flux from an unillustrated object defined as anobject to be imaged is collected by the imaging lens 2, and an image isformed on a focusing screen 4 via a quick return mirror 3. The lightforming the image on the focusing screen 4, is reflexed a plural numberof times within a pentaprism 5 and guided to an eyepiece 6. Theoperation being thus performed, a photographer can observe the image ofthe object as an erect image via the eyepiece 6.

Further, when the photographer depresses an unillustrated releasebutton, the quick return mirror 3 retreats off a light path, and thelight traveling from the unillustrated object reaches an imaging device7. The light from the object is thereby imaged by the imaging device 7,and the captured image is recorded as the image of the object on anunillustrated memory. Thus, the photographer can capture the image ofthe object through the camera 1.

Herein, the zooming optical system mounted as the imaging lens 2 in thecamera 1 according to the first Example is, as described above, compactand has the vibration reduction function, the high zooming ratio, thewide-angle view and the superb optical performance. The camera 1 isthereby enabled to realize the superb optical performance while havingthe vibration reduction function, the high zooming ratio and thewide-angle view and being scaled down. Note that the same effects asthose of the camera 1 can be exhibited even by building up a cameramounted with the zooming optical system according to each of the secondto sixth Examples as the imaging lens 2. Moreover, the same effects asthose of the camera 1 can be exhibited even by mounting the zoomingoptical system according to each of the Examples on a camera configurednot to include the quick return mirror 3.

Finally, an outline of a method for manufacturing the zooming opticalsystem according to each of the first to third embodiments of thepresent application will be described based on FIGS. 20-22 .

The method for manufacturing the zooming optical system as illustratedin FIG. 20 according to the first embodiment of the present applicationis a method for manufacturing the zooming optical system including, inorder from an object side, a first lens group having positive refractivepower, a second lens group having negative refractive power, a thirdlens group having positive refractive power and a fourth lens grouphaving positive refractive power, the method including the followingsteps S11-S14:

Step S11 of constructing the third lens group to include, in order fromthe object side, a first segment group having positive refractive powerand a second segment group.

Step 12 of constructing the first lens group and the second lens groupsuch that the following conditional expression (1) may be satisfied:8.00<f1/(−f2)<10.00  (1)where f1 denotes a focal length of the first lens group, and f2represents a focal length of the second lens group, and disposing thefirst to fourth lens groups within a lens barrel in order from theobject side,

Step S13 of constructing such that an air distance between the firstlens group and the second lens group, an air distance between the secondlens group and the third lens group and an air distance between thethird lens group and the fourth lens group may be varied respectivelyupon zooming to the telephoto end state from the wide-angle end state byproviding a known moving mechanism within the lens barrel, and

Step 14 of constructing the second segment group to move in a directionhaving a component perpendicular to the optical axis by providing aknown moving mechanism within the lens barrel.

The method for manufacturing the zooming optical system according to thefirst embodiment of the present application enables a compact zoomingoptical system to be manufactured, which has the vibration reductionfunction, the high zooming ratio, the wide-angle view and the superboptical performance.

The method for manufacturing a zooming optical system as illustrated inFIG. 21 according to the second embodiment of the present application isa method for manufacturing a zooming optical system including, in orderfrom an object side, a first lens group having positive refractivepower, a second lens group having negative refractive power, a thirdlens group having positive refractive power and a fourth lens grouphaving positive refractive power, the method including the followingsteps S21-S24:

Step S21 of constructing the third lens group to include, in order fromthe object side, a first segment group having positive refractive powerand a second segment group,

Step 22 of constructing the first lens group and the third lens groupsuch that the following conditional expression (3) may be satisfied:2.80<f1/f3<4.50  (3)where f1 denotes a focal length of the first lens group, and f3represents a focal length of the third lens group, and disposing thefirst to fourth lens groups within a lens barrel in order from theobject side,

Step S23 of constructing, by providing a known moving mechanism withinthe lens barrel, such that an air distance between the first lens groupand the second lens group, an air distance between the second lens groupand the third lens group and an air distance between the third lensgroup and the fourth lens group respectively varied, upon zooming to thetelephoto end state from the wide-angle end state, and

Step 24 of constructing the second segment group to move in a directionhaving a component perpendicular to the optical axis by providing aknown moving mechanism within the lens barrel.

The method for manufacturing the zooming optical system according to thesecond embodiment of the present application enables a compact zoomingoptical system to be manufactured, which has the vibration reductionfunction, the high zooming ratio, the wide-angle view and the superboptical performance.

The method for manufacturing the zooming optical system as illustratedin FIG. 22 according to the third embodiment of the present applicationis a method for manufacturing the zooming optical system including, inorder from the object side, a first lens group having positiverefractive power, a second lens group having negative refractive power,a third lens group having positive refractive power and a fourth lensgroup having positive refractive power, the method including thefollowing steps S31-S34:

Step S31 of constructing the third lens group to include, in order froman object side, a first segment group having positive refractive powerand a second segment group,

Step 32 of constructing the first lens group and the third lens groupsuch that the following conditional expressions (5) and (7) may besatisfied:0.20<f32/f1<0.43  (5)0.60<f31/f3<0.90  (7)where f1 denotes a focal length of the first lens group, f3 represents afocal length of the third lens group, f31 denotes a focal length of thefirst segment group, and f32 represents a focal length of the secondsegment group, and disposing the first to fourth lens groups within alens barrel in order from an object side,

Step S33 of constructing such that an air distance between the firstlens group and the second lens group, an air distance between the secondlens group and the third lens group and an air distance between thethird lens group and the fourth lens group respectively varied uponzooming to the telephoto end state from the wide-angle end state byproviding a known moving mechanism within the lens barrel, and

Step 34 of constructing the second segment group to move in a directionhaving a component perpendicular to the optical axis by providing aknown moving mechanism within the lens barrel.

The method for manufacturing the zooming optical system according to thethird embodiment of the present application enables a compact zoomingoptical system to be manufactured, which has the vibration reductionfunction, the high zooming ratio, the wide-angle view and the superboptical performance.

What is claimed is:
 1. A zooming optical system comprising, in orderfrom an object side: a first lens group having positive refractivepower; a second lens group having negative refractive power; a thirdlens group having positive refractive power; and a fourth lens grouphaving positive refractive power; upon zooming from a wide-angle endstate to a telephoto end state, all distances between adjacent lensgroups of the zooming optical system being varied and said first lensgroup being moved toward the object side; said third lens groupcomprising, in order from the object side, a first segment group havingpositive refractive power and a second segment group having negativerefractive power; said second segment group being movable in a directionhaving a component perpendicular to an optical axis; said first lensgroup including, at the most object side, a cemented lens composed of,in order from the object side, a negative lens and a positive lens; saidfourth lens group consisting of one singlet lens and one cemented lens;and the following conditional expression being satisfied:3.00<f1/f3<4.50 where f1 denotes the focal length of the entire firstlens group, and f3 denotes the focal length of the entire third lensgroup.
 2. The zooming optical system according to claim 1, wherein thefollowing conditional expression is satisfied:0.20<|f32|/f1<0.43 where f32 denotes the focal length of the entiresecond segment group.
 3. The zooming optical system according to claim1, wherein said third lens group includes a positive singlet lensdisposed at the most object side.
 4. The zooming optical systemaccording to claim 1, wherein said first segment group of said thirdlens group consists of, in order from the object side, a positivesinglet lens and a cemented lens.
 5. The zooming optical systemaccording to claim 1, wherein said second segment group of said thirdlens group consists of one lens component.
 6. The zooming optical systemaccording to claim 1, wherein an aperture stop is provided on the objectside of said third lens group.
 7. The zooming optical system accordingto claim 1, wherein said second lens group moves toward the object sideupon zooming to the telephoto end state from the wide-angle end state.8. The zooming optical system according to claim 1, wherein said thirdlens group moves toward the object side upon zooming to the telephotoend state from the wide-angle end state.
 9. The zooming optical systemaccording to claim 1, wherein at least a part of said second lens groupmoves when focusing.
 10. The zooming optical system according to claim1, wherein the following conditional expression is satisfied:8.00<f1/(−f2)<10.00 where f2 denotes the focal length of the entiresecond lens group.
 11. The zooming optical system according to claim 1,wherein the following conditional expression is satisfied:0.60<f3/f4<0.90 where f4 denotes the focal length of the entire fourthlens group.
 12. The zooming optical system according to claim 1, whereinthe following conditional expression is satisfied:2.20<f1/f4<3.50 where f4 denotes the focal length of the entire fourthlens group.
 13. The zooming optical system according to claim 1, whereinthe following conditional expression is satisfied:0.35<(−f2)/f3<0.55 where f2 denotes the focal length of the entiresecond lens group.
 14. An optical apparatus comprising said zoomingoptical system according to claim
 1. 15. A method for manufacturing azooming optical system comprising, in order from an object side: a firstlens group having positive refractive power; a second lens group havingnegative refractive power; a third lens group having positive refractivepower; and a fourth lens group having positive refractive power; saidmethod comprising steps of: constructing the third lens group tocomprise, in order from the object side, a first segment group havingpositive refractive power and a second segment group having negativerefractive power, constructing said first lens group to include, at themost object side, a cemented lens composed of, in order from the objectside, a negative lens and a positive lens, constructing said fourth lensgroup to consist of one singlet lens and one cemented lens, constructingthe first lens group and the third lens group such that the followingconditional expression is satisfied:3.00<f1/f3<4.50 where f1 denotes the focal length of the entire firstlens group, and f3 denotes the focal length of the entire third lensgroup, constructing such that, upon zooming to a telephoto end statefrom a wide-angle end state, all distances between adjacent lens groupsof the zooming optical system are varied and said first lens group ismoved toward the object side, and constructing such that the secondsegment group can move in a direction having a component perpendicularto an optical axis.